Standard Bank declined extended bond for no apparent reason

I submitted an application for an extended bond around September 2019. A lot of documents and information was requested from me, which required a lot of my precious time and effort. A valuation of the property was done and the bank was offering an extended bond of up to R1000 000. I disputed this amount and requested for a revaluation. A second valuation was done and this time around the property was valued at R1500 000. After a few days of waiting for the Bank to grant the loan, I was then advised that the application is declined due to the property being multi tenanted.

I went to a different Bank and they have approved a extended bond and in the process of moving my bond from Standard Bank. I've been a Standard Bank customer for many years however should all go well, I will be moving the rest of my accounts from Standard Bank.

I would like Standard Bank to explain why they refused to grant the loan after the second valuation? Note affordability was not an issue.